Barbiturates classification

Classification Barbiturates Preoperative Indication Decrease anxiety facilitate induction of anesthesia Drug Amobarbital Butabarbital Pentobarbital Phenobarbital Secobarbital Method of Administration Oral 200 mg 1 to 2 hours before surgery Oral 50-100 mg 60 to 90 minutes before surgery Oral 100 mg IM 150-200 mg IM 130-200 mg 60 to 90 minutes before surgery Oral 200-300 mg 1 to 2 hours before surgery... 

The classification of barbiturates as ultrashort-acting, short-acting, intermediate-acting, and long-acting refers to the duration of effect and not to the elimination half-life. The duration of action is determined by the rate of distribution into brain and subsequent redistribution to other tissues. ... 

In some cases (e.g. penicillins) this is a useful classification since the biological activity (e.g. antibiotic activity for penicillins) is the same. However, there is a danger that one could be confused into thinking that all compounds of a certain chemical group have the same biological action. For example, barbiturates may look much alike and yet have completely different uses in medicine. The same holds true for steroids. 

Insect GABARs do not fit into the vertebrate classification, because most are simultaneously insensitive to the GABAA-diagnostic antagonist bicucculine but sensitive the GABAA-specific benzodiazepines and barbiturates. Bicucculine-sensitive receptors that are sensitive to allosteric modulators of GABAa receptors have also been observed in insects [26]. 

Fig. 2 Classification of supramolecular building blocks functionalized with hydrogen-bonding groups (HBGs) and a few examples of self-complementary and heterocomplementary binding motifs. BTA benzene-1,3,5-tricarboxyamide, UPy ureidopyrimidinone, DATdiamino triazine. Thy thymine, Napy 2,7-diaminonaphtyriine, Ba barbituric acid, HR hamilton receptor...

A set of 160 barbiturates was coded using 46 molecular descriptors, including fragments, substructures, environmental descriptors, and a molecular connectivity index C287, 288, 2921. Classifiers were developed with a learning machine that recognizes the duration of the depressant effect- Predictive abilities of 94 % were reported for correct classifications of the duration time "less than t minutes". 

According to the 1964 WHO classification there are 7 groups 1. alkaloids (LSD, mescalin, opium, etc.), 2. barbiturates and other sleeping drugs, 3. alcohol, 4. cocaine, 5. hashish and marihuana, 6. halludl-logens, 7. stimulants or antidepressants (e.g. amphetamines). 

---